title: Laryngeal electromyography as a diagnostic tool for Parkinson's disease.
abstract: OBJECTIVE
  To study the laryngeal electromyography pattern in patients with Parkinson's disease (PD) and vocal complaints at different stages of the disease.
  
  
  METHODS
  Cross-sectional cohort study.
  
  
  METHODS
  Ninety-four adults with PD and vocal complaints at different stages of the disease (according to the Hoehn and Yahr scale) underwent laryngeal electromyography.
  
  
  RESULTS
  Tremors were not detected on laryngeal electromyography of the cricothyroid and thyroarytenoid muscles even in patients with clinical tremor. Laryngeal electromyography hypercontractility during voice rest was the typical result observed in 91.5% of patients regardless of disease severity. Gender and age of subjects did not correlate with laryngeal electromyography results. Patients with PD presented spontaneous intrinsic laryngeal muscle activity during voice rest, regardless of disease severity.
  
  
  CONCLUSIONS
  This study was significant because it reported on the use of laryngeal electromyography in a large number of patients with PD and vocal complaints grouped according to PD severity. The patterns observed suggest that laryngeal electromyography is a valuable diagnostic tool for PD even at early phases of the disease.
authors.affiliation: Department of Otolaryngology, Medical Science Faculty, Santa Casa de São Paulo Hospital, São Paulo, Brazil.
authors.forename: Ana P
authors.initials: AP
authors.lastname: Zarzur
authors.forename: André de Campos
authors.initials: Ade C
authors.lastname: Duprat
authors.forename: Berenice O
authors.initials: BO
authors.lastname: Cataldo
authors.forename: Daniel
authors.initials: D
authors.lastname: Ciampi
authors.forename: Erich
authors.initials: E
authors.lastname: Fonoff
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D018450:Disease Progression; D004576:Electromyography / Q000379:methods*; D005260:Female; D006801:Humans; D007821:Laryngeal Muscles / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D009126:Muscle Relaxation / Q000502:physiology; D010300:Parkinson Disease / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012720:Severity of Illness Index; D014202:Tremor / Q000175:diagnosis / Q000188:drug therapy; D014832:Voice Disorders / Q000175:diagnosis* / Q000209:etiology / Q000628:therapy
keywords: Electromyography; Parkinson's disease; laryngeal muscle